APA (7th ed.) Citation

Inglis, J., & Lewis, R. (1980). Clear thinking: An introduction. National Extension College.

Chicago Style (17th ed.) Citation

Inglis, John, and Roger Lewis. Clear Thinking: An Introduction. Cambridge: National Extension College, 1980.

MLA (9th ed.) Citation

Inglis, John, and Roger Lewis. Clear Thinking: An Introduction. National Extension College, 1980.